[PATCH] perf: build reproducibility improvements

From: Denys Zagorui
Date: Fri Mar 12 2021 - 10:24:57 EST


This patch helps to make perf build more reproducible

It seems there is some need to have an ability to invoke
perf from build directory without installation
(84cfac7f05e1: perf tools: Set and pass DOCDIR to builtin-report.c)
DOCDIR contains an absolute path to kernel source directory.
In such case this path can be determined in runtime by using
/proc/self/exe link. In case of building perf with O=
Documentation/tips.txt can be copied to output directory.

There is also python binding test where PYTHONPATH is used to store
absolute path to python/perf.so library. This path can be
also determined in runtime.

bison stores full paths in generated files. This can be
remapped by using --file-prefix-map option that is available
starting from version 3.6.3.

Signed-off-by: Denys Zagorui <dzagorui@xxxxxxxxx>
---
tools/lib/subcmd/exec-cmd.c | 21 +++++++++++++++++++++
tools/lib/subcmd/exec-cmd.h | 1 +
tools/perf/Build | 1 -
tools/perf/Makefile.perf | 3 +++
tools/perf/builtin-report.c | 21 ++++++++++++++++++---
tools/perf/tests/Build | 2 +-
tools/perf/tests/python-use.c | 14 +++++++++++++-
tools/perf/util/Build | 10 +++++++---
8 files changed, 64 insertions(+), 9 deletions(-)

diff --git a/tools/lib/subcmd/exec-cmd.c b/tools/lib/subcmd/exec-cmd.c
index 33e94fb83986..9c293a810159 100644
--- a/tools/lib/subcmd/exec-cmd.c
+++ b/tools/lib/subcmd/exec-cmd.c
@@ -208,3 +208,24 @@ int execl_cmd(const char *cmd,...)
argv[argc] = NULL;
return execv_cmd(argv);
}
+
+/* The caller is responsible to free the returned buffer */
+char *get_exec_abs_path(void)
+{
+ int ret;
+ int i;
+ char *buf;
+
+ buf = malloc(PATH_MAX);
+ ret = readlink("/proc/self/exe", buf, PATH_MAX - 1);
+ if (ret <= 0) {
+ free(buf);
+ return NULL;
+ }
+
+ for (i = ret - 1; buf[i] != '/'; i--)
+ ; /* just counting */
+ buf[i + 1] = 0;
+
+ return buf;
+}
diff --git a/tools/lib/subcmd/exec-cmd.h b/tools/lib/subcmd/exec-cmd.h
index aba591b8d254..9dc98248dadf 100644
--- a/tools/lib/subcmd/exec-cmd.h
+++ b/tools/lib/subcmd/exec-cmd.h
@@ -13,5 +13,6 @@ extern int execl_cmd(const char *cmd, ...);
/* get_argv_exec_path and system_path return malloc'd string, caller must free it */
extern char *get_argv_exec_path(void);
extern char *system_path(const char *path);
+extern char *get_exec_abs_path(void);

#endif /* __SUBCMD_EXEC_CMD_H */
diff --git a/tools/perf/Build b/tools/perf/Build
index db61dbe2b543..56d0189f1029 100644
--- a/tools/perf/Build
+++ b/tools/perf/Build
@@ -45,7 +45,6 @@ CFLAGS_perf.o += -DPERF_HTML_PATH="BUILD_STR($(htmldir_SQ))" \
-DPREFIX="BUILD_STR($(prefix_SQ))"
CFLAGS_builtin-trace.o += -DSTRACE_GROUPS_DIR="BUILD_STR($(STRACE_GROUPS_DIR_SQ))"
CFLAGS_builtin-report.o += -DTIPDIR="BUILD_STR($(tipdir_SQ))"
-CFLAGS_builtin-report.o += -DDOCDIR="BUILD_STR($(srcdir_SQ)/Documentation)"

perf-y += util/
perf-y += arch/
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index f6e609673de2..2bebff69b064 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -627,6 +627,9 @@ $(OUTPUT)python/perf.so: $(PYTHON_EXT_SRCS) $(PYTHON_EXT_DEPS) $(LIBTRACEEVENT_D
--quiet build_ext; \
cp $(PYTHON_EXTBUILD_LIB)perf*.so $(OUTPUT)python/

+_dummy := $(shell [ -d '$(OUTPUT)Documentation' ] || mkdir -p '$(OUTPUT)Documentation' && \
+ cp '$(srcdir)/Documentation/tips.txt' '$(OUTPUT)Documentation/')
+
please_set_SHELL_PATH_to_a_more_modern_shell:
$(Q)$$(:)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 2a845d6cac09..d9441055357e 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -610,12 +610,27 @@ static int report__browse_hists(struct report *rep)
struct perf_session *session = rep->session;
struct evlist *evlist = session->evlist;
const char *help = perf_tip(system_path(TIPDIR));
+ char *exec_path;
+ char *docdir;

if (help == NULL) {
/* fallback for people who don't install perf ;-) */
- help = perf_tip(DOCDIR);
- if (help == NULL)
- help = "Cannot load tips.txt file, please install perf!";
+ exec_path = get_exec_abs_path();
+ if (exec_path == NULL || asprintf(&docdir, "%sDocumentation", exec_path) < 0) {
+ docdir = NULL;
+ help = "Not enough memory or some other internal error occurred!";
+ }
+
+ if (docdir != NULL) {
+ help = perf_tip(docdir);
+ if (help == NULL)
+ help = "Cannot load tips.txt file, please install perf!";
+ }
+
+ if (exec_path)
+ free(exec_path);
+ if (docdir)
+ free(docdir);
}

switch (use_browser) {
diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 650aec19d490..a20098dcdbc4 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -98,5 +98,5 @@ perf-$(CONFIG_DWARF_UNWIND) += dwarf-unwind.o
endif

CFLAGS_attr.o += -DBINDIR="BUILD_STR($(bindir_SQ))" -DPYTHON="BUILD_STR($(PYTHON_WORD))"
-CFLAGS_python-use.o += -DPYTHONPATH="BUILD_STR($(OUTPUT)python)" -DPYTHON="BUILD_STR($(PYTHON_WORD))"
+CFLAGS_python-use.o += -DPYTHON="BUILD_STR($(PYTHON_WORD))"
CFLAGS_dwarf-unwind.o += -fno-optimize-sibling-calls
diff --git a/tools/perf/tests/python-use.c b/tools/perf/tests/python-use.c
index 98c6d474aa6f..8b4865c90d5d 100644
--- a/tools/perf/tests/python-use.c
+++ b/tools/perf/tests/python-use.c
@@ -8,16 +8,28 @@
#include <linux/compiler.h>
#include "tests.h"
#include "util/debug.h"
+#include <subcmd/exec-cmd.h>

int test__python_use(struct test *test __maybe_unused, int subtest __maybe_unused)
{
char *cmd;
int ret;
+ char *exec_path = NULL;
+ char *pythonpath;
+
+ exec_path = get_exec_abs_path();
+ if (exec_path == NULL)
+ return -1;
+
+ if (asprintf(&pythonpath, "%spython", exec_path) < 0)
+ return -1;

if (asprintf(&cmd, "echo \"import sys ; sys.path.append('%s'); import perf\" | %s %s",
- PYTHONPATH, PYTHON, verbose > 0 ? "" : "2> /dev/null") < 0)
+ pythonpath, PYTHON, verbose > 0 ? "" : "2> /dev/null") < 0)
return -1;

+ free(exec_path);
+ free(pythonpath);
pr_debug("python usage test: \"%s\"\n", cmd);
ret = system(cmd) ? -1 : 0;
free(cmd);
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index e3e12f9d4733..05454c6340e5 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -197,6 +197,10 @@ CFLAGS_llvm-utils.o += -DPERF_INCLUDE_DIR="BUILD_STR($(perf_include_dir_SQ))"
# avoid compiler warnings in 32-bit mode
CFLAGS_genelf_debug.o += -Wno-packed

+ifeq ($(shell expr $(shell $(BISON) --version | grep bison | sed -e 's/.\+ \([0-9]\+\).\([0-9]\+\).\([0-9]\+\)/\1\2\3/g') \>\= 363), 1)
+ BISON_FILE_PREFIX_MAP := --file-prefix-map=$(OUTPUT)=
+endif
+
$(OUTPUT)util/parse-events-flex.c $(OUTPUT)util/parse-events-flex.h: util/parse-events.l $(OUTPUT)util/parse-events-bison.c
$(call rule_mkdir)
$(Q)$(call echo-cmd,flex)$(FLEX) -o $(OUTPUT)util/parse-events-flex.c \
@@ -204,7 +208,7 @@ $(OUTPUT)util/parse-events-flex.c $(OUTPUT)util/parse-events-flex.h: util/parse-

$(OUTPUT)util/parse-events-bison.c $(OUTPUT)util/parse-events-bison.h: util/parse-events.y
$(call rule_mkdir)
- $(Q)$(call echo-cmd,bison)$(BISON) -v $< -d $(PARSER_DEBUG_BISON) \
+ $(Q)$(call echo-cmd,bison)$(BISON) -v $< -d $(PARSER_DEBUG_BISON) $(BISON_FILE_PREFIX_MAP) \
-o $(OUTPUT)util/parse-events-bison.c -p parse_events_

$(OUTPUT)util/expr-flex.c $(OUTPUT)util/expr-flex.h: util/expr.l $(OUTPUT)util/expr-bison.c
@@ -214,7 +218,7 @@ $(OUTPUT)util/expr-flex.c $(OUTPUT)util/expr-flex.h: util/expr.l $(OUTPUT)util/e

$(OUTPUT)util/expr-bison.c $(OUTPUT)util/expr-bison.h: util/expr.y
$(call rule_mkdir)
- $(Q)$(call echo-cmd,bison)$(BISON) -v $< -d $(PARSER_DEBUG_BISON) \
+ $(Q)$(call echo-cmd,bison)$(BISON) -v $< -d $(PARSER_DEBUG_BISON) $(BISON_FILE_PREFIX_MAP) \
-o $(OUTPUT)util/expr-bison.c -p expr_

$(OUTPUT)util/pmu-flex.c $(OUTPUT)util/pmu-flex.h: util/pmu.l $(OUTPUT)util/pmu-bison.c
@@ -224,7 +228,7 @@ $(OUTPUT)util/pmu-flex.c $(OUTPUT)util/pmu-flex.h: util/pmu.l $(OUTPUT)util/pmu-

$(OUTPUT)util/pmu-bison.c $(OUTPUT)util/pmu-bison.h: util/pmu.y
$(call rule_mkdir)
- $(Q)$(call echo-cmd,bison)$(BISON) -v $< -d $(PARSER_DEBUG_BISON) \
+ $(Q)$(call echo-cmd,bison)$(BISON) -v $< -d $(PARSER_DEBUG_BISON) $(BISON_FILE_PREFIX_MAP) \
-o $(OUTPUT)util/pmu-bison.c -p perf_pmu_

FLEX_GE_26 := $(shell expr $(shell $(FLEX) --version | sed -e 's/flex \([0-9]\+\).\([0-9]\+\)/\1\2/g') \>\= 26)
--
2.23.1